Use advisory_lock from DAB (#15676)

* Use advisory_lock from DAB

* Remove the django-pglocks dep

* Re-run updater script

* Move the import in new location

awx/main/models/credential.py

@@ -23,9 +23,11 @@ from django.contrib.auth.models import User
 
 
 # DRF
-from awx.main.utils.pglock import advisory_lock
 from rest_framework.serializers import ValidationError as DRFValidationError
 
+# django-ansible-base
+from ansible_base.lib.utils.db import advisory_lock
+
 # AWX
 from awx.api.versioning import reverse
 from awx.main.fields import (